The principal stabiliser of the medial side of the ankle joint against eversion stress is:
- A Anterior talofibular ligament
- B Deltoid (medial collateral) ligament ✓
- C Calcaneofibular ligament
- D Spring (plantar calcaneonavicular) ligament
Correct answer: B. Deltoid (medial collateral) ligament
Explanation
The deltoid ligament is a strong, fan-shaped medial collateral ligament of the ankle consisting of superficial (tibiocalcaneal, tibionavicular, posterior tibiotalar) and deep (anterior tibiotalar, posterior tibiotalar) components. It is the primary restraint to eversion (and external rotation) of the talus. Its strength is why eversion sprains are less common than inversion sprains; indeed, forced eversion more often avulses the medial malleolus than ruptures the deltoid. The anterior talofibular and calcaneofibular ligaments are lateral ligaments resisting inversion.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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